Illegal boxing matches were staged on the island in the late 19th century.[1]

In the 1920s, the Army planned to install a pair of 16-inch (410 mm) guns on Calf Island as part of the
Harbor Defenses of Boston, along with 16-inch (410 mm) gun batteries on Deer Island (now underneath the
Deer Island Waste Water Treatment Plant) and Hog Island (now called Spinnaker Island), to cover the seaward approaches to Boston Harbor. The battery on Calf Island was never built.[1]